Inclinometer for airplanes



July 17, 1934. Q T H 1,966,714

INCLINOMETER FOR AIRPLANES Filed May 16, 1932 f jIYI ENTOR. 2; 2%

A TTORNE Y.

Patented July 17, 1934 UNITED STATES PATENT OFFICE 1 Claim.

This invention relates to inclinometers for airplanes, and the chief object of the invention is to provide anovel, relatively simple and practical device for the purpose of indicating both the longitudinal and lateral inclination of the plane during its flight, and especially in the night time or while flying through cloud banks or heavy fog.

Another object is to provide a device of the kind referred to, the same including two assemblies of gravity controlled sprockets and chains arranged in different planes, with markers or indicators on the chains, whereby the longitudinal 0T. lateral inclination of the plane may be readily shown.

With these and such other objects in view as may be disclosed in the following specification, attention is directed to the accompanying drawing as illustrating a preferred embodiment of my invention, and wherein Figure 1 is a frontal elevation of the invention as same appears properly housed.

Figure 2 is a longitudinal section on the line 2-2 of Figure 1.

Figure 3 is an enlarged, fragmental, longitudinal sectional view on the line 3-3 of Figure 1, portions of the outer casing being broken away.

Figure 4 is a transverse section on the line 4- 1 of Figure 3.

Figure 5 is a section on the line 5-5 of Figure 3, portions of the outer casing being broken away.

The invention comprises a suitable outer casing 1, including a face plate 2, top 3, bottom 4, sides 5 and rear end 6. The face plate is extended at its. margins 7 and pierced with screw holes 8 as means for fastening the apparatus in suitable position upon an airplane (not shown), where the said face plate is to be vertically positioned. The said face plate is also .pierced medially with a vertically elongated window or slot 9 which may be designated as the longitudinal dip slot, and with a horizontally elongated window or slot 10 positioned below the slot 9, and which, may be designated as the lateral dip slot. Within the lower part of the outer casing 1 are mounted two horizontally. arranged and spaced webs 11, the same being flanged at their side margins and anchored to the sides of the outer casing as indicated at 12. Additionally, two vertically arranged and spaced webs 13 are medially and longitudinally mounted within the casing 1, upon 5 the uppermost web 11, the said webs 13 being secured in place by flanging their side margins and anchoring said flanges to the top 3 and web 11, as shown at 14.

Within the lower partition 15 formed by the spaced webs 11, is mounted the lateral dip o sprocket zssembly, the same including three sprockets 16 and 16 mounted upon shafts 17 and 17 vertically extended between the webs 11 and journaled therein at their ends. These sprockets are all arranged to rotate in a com- 5 mon horizontal plane, the two equal sprockets 16 being disposed at either end of the lateral dip slot 10, and the third sprocket 16' being larger in diameter and located at a spaced distance in the rear of the other two. A bevel gear 18 is 7 rigidly mounted upon the rear shaft 17' above the sprocket 16. A shaftyl9 is horizontally journaled at 20 through an. end bearing 21 mounted between the rear ends of the webs 11, and a bevel gear 22 is rigidly mounted upon the inner end thereof, in mesh with the gear 18. A weight 23 is depended from the outer end of the shaft 19. A sprocket chain 24 is mounted over the three sprockets 1616' and a plurality of markers or indicators 25 are extended from the. 30 chain at regularly spaced intervals.

Within the upper partition 26 formed by the spaced vertical webs 13, there is arranged a longitudinal dip assembly, the same including a set of three sprockets 27-27', similar to the g5 sprockets 16-16, except that they are vertically arranged. The two frontal sprockets 27 are mounted upon shafts 23' which have their ends journaled in the said webs 13 immediately back of the slot 9 and at either end thereof, 99 and the sprocket 27' is likewise mounted upon a shaft 28' having its ends journaled in the said webs.- A sprocket chain 29 is also disposed, over these sprockets and a number of indicators 30 are located in equi-spaced relation thereupon. In practice, it is best to provide an equal number of indicators for'both the horizontal and vertical sprocket assemblies. The rear sprockets should have a circumference of approximately one-third the length of the chains, so that one complete revolution of those sprockets would serve to replace any indicators at the front window slots, with another one of the three indicators on each chain. Thus upon a complete turn over of the plane either longitudinally or laterally, an indicator would nevertheless stand correctly positioned at each slot. Likewise, should an indicator be broken off through any cause, the aviator. could readily replace it by merely rotating the rear sprockets 11o one turn. The provision. of for the weiahts, enables indicators closely as wanted slots for ready t'iQTJ. 3c for the dip assembly, l to he set to provide swini ng the weight.

The elements are so arranged and adjusted that when the case 1 is roperly mounted upon an airplane (not shown), the latter being evenly or normally positioned as at rest, the face plate 2 will stand perpendicularly to the surface of the earth, and under the action of the weights 23 and 31 one of each set of indicators 25 and 30, will stand midway of the slots 9 and ill, or at zero marks as shown in Figure 1. In the course of flight, it will be apparent that, under the action of the weights, as the plane dips in a, longitudinal direction, the frontal indicator 30 of the longitudinal dip assembly inove correspondingly from zero position, either above or below the same as the nose the plane falls rises, and similarly the frontal indicator 25 c2": the lateral dip assembly room for will move to the right or left of its zero posi tion, as the plane dips to the right or left. Thus th pilot may know at all times the exact condition of the plane as to balance or angularity of flight.

While I have herein described a certain specific manner and method of constructing and assembling the elements of my invention, it is understood that I may vary from the same in minor details, not departing from the spirit of invention, so as best to construct a practical device for the purpose intended, as defined in the appended claim.

claim:

in a device of the kind described, a frame, three sprockets mounted upon the frame in a triangular relation and arranged to rotate in a common plane, a sprocket chain trained over the sprockets, and three indicators mounted in equi-spaced relation along the chain, the circumference of one of the sprockets being equal to one-third the length of the chain.

CYRUS O. FRITSCH.

yen 

